System



R. E. HELLMUND AND H. T. MORRIS. SYSTEM OF CONTROL.

APPLICATION FILED MAR.I3,1916- 1,31 1,859.

Valley 2 SHEETS-SHEET f7 2 Rudy/f 5 e /mz//7d [4d 7 *Humg Z Mar/73 Patented July 29, 1919.

R. E. HELLMUND AND H. T. MORRIS.

SYSTEM OF CONTROL. APPLICATION FILED MAR. 13, 1915.

Patented July '29, 1919.

2 SHEETS-SHEET 2.

Ema/f Z. $5223.51 h /0rd 7 Mar/73 BY Q W TNESSES r ATTORNEY RUDOLF E. HELLMUND, OF PITTSBURGH, AND HU'RD '1. M

PENNSYLVANIA, ASSIG-NORS TO WETLNGEOUSEELECTRIC AND ING COMPANY, A. CORPORATION 02 PENNSYLVANIA SYSTEK OF CONTROL.

Specification of Letters Patent.

Applicaton filed larch 1a, 1916. swarm).

s arkless operation and, werethis attempted with the system of said prior application, there are two sequences of operation powible and, furthermore, ere is a tendenc to run ahead of the master controller and to give a jerky and with unsatisfactory ternating-current motors of the com- By the present invention, we

e. means whereby the ch of our invention is to provide a fed operation e above-indicated character a which shall embody certain vnovel features said change-over 1s effected, transition will for effecting more reliable and satisfactory al operation of the system. connection and,

eretofore, in systems of the type emp oying alternating-current, commutator consequent lack of abrupt changes motors that are initially connected as rep-uler novel control features of our system hereinafter pointed out. it has been In the accompanying drawings, Figure 1 hroughout, whereby there is -no assurance that the ange to a doubly-fed connection is effected under proper or permissible commutating conditions, or to completely automatically control the system, wh

by relatively expensive and complicated systems have obtained.

11 a prior application of H. T. Serial N 0. 32,183, filed June Morris, 4, 1915, and control apparatus that are emp nection with inclusive, main-circuit connections that during the operation of the motors.

tors of the compensated,commutator t pe Ref drawing, the are started and manually accelerated as repulsion motors and are automatically respectively changed over to doubly-fed motors by a Trolley and Ground a trans- T provided with a primary winding winding S acceleration as doubly-fed ound that,

disastrous sparking. Furthermore, under doubly-fed acceleration will tie effected with 1 pair of suit-- -ings AF3 and A2, B1, B2, c1, c2,

- in P of the transformer to 't employed governing system armatures M3 and M4, exciting field windings F3 and F4 and commutating field wind- AF4, all of the motors being adapted for operation from the secondary winding S of the transformer; a plurality of reversing-switchesRSl and RS2, preferably of the familiar electricall -controlled drum type, for respectively s' ultaneously reversing the electrical relations of the several pairs of motors,

a plurality controlling swltches 1 to'8, inclusive, A1, R1 and R2, :1. suitable switch LS for connecting the primary wind e supply circult, a plurality of limit switches L1 and L2 of the differential type, having their main or repondera-ting actuating coils respective y disposed in circuit with the commutating field windings of the several. pairsof motors and having their opposing o'r subordinate windings connected in parallel relationk to the operating coil of the switch 1; a plurality of resistors RC1 and RC2 that are for short-circuiting the pairs of M1 and M2 and and a plurality n31, BB2, ARI

series-connected armatures M3 and M4, respectively; of accelerating resistors, and AR2.

Referring now to Fig. 2, the auxiliary shown comprises, in a dition to the actuating coils for the various motor-controlling switches and the electrical interlocks of a familiar character that are respectively associated with certain of the switches, as illustrated in Fig. 4, a master controller MC that is adapted to occupy a plurality of operative positions a to g, inclusive, a master reverser of a familiar type; a suitable source of energy, such as a battery, B, for supplying. energy through the master reverser and master controller to the various actuatingcoils; the auxiliary contact members of the limit switches L1 and L2, and a plurality of train-line conductors TL respectively corresponding to the several positions of the master controller, in accordance with customary practice.

In addition to the electrical interlocks that are movable with respective motor-controlling switches, a plurality of similar interlocks or contact members (IO-16, inclusive, are disposed upon a change-over or cut-out drum CO for the motors, as diagrammatically illustrated in Fig. 5. The drum is adapted to occupy a plurality of positions, as indicated by the respective legends that are employed in the figure. 7

Assuming that the switch LS is closed, that the change-over switch CO occupies its position marked All-in; that the master the system may be set forth as follows: A

of motorand RC2 being connected across ment 24 through circuit is first established from one terminal of the battery B through conductors 20 and 21, control-fingers 22 and 23.which are bridged by contactsegment 24 of the master controller-conductor 25, control fingers 26 and 27--which are bridged by. contact segs ment 28 of the master revcrser-.conductor 29, trai line conductor 30, conductor 31, contact segment 33' of the reversing switch BS, in its forward position, conductors 34 and 35, interlock CO-12-All-in, the actu-. atin coils of the switches A1 and 7 and con uctors 36 and 37 to the opposite terminal of the battery simultaneously established fromrconductor 30 through conductor 38, contact segment 39 of the main reversing switch RS, conductors 40 and 41, interlock C( )--11'Allin and the actuating coils of the switches A2 and 8 to the negative conductor 36.

A further circuit is completed from contact segment 42 of the master controller throu h control finger 43, conductor 44, trainine conductor 45 conductor 46, interlock 2-out, conductor 4 and 48, and the actuating coil of the switch 1 to conductor 36.

Another circu't is established, at the same and-3-out, conductor 47' and the parallel- B. Another circuit is connected actuat ng coils of the switches C1 and C2 to conductor 36.

The motors are thus started into operation as repulsion motors, the resistors the pairs d M2, and M3 and the parallel-connected of armatures M1 an respectively, and

pairs of motors are respectively connected in series-circuit relation, with the accelerat ing resistors BR1and'RR2 across a suitable portion of the secondary winding S of the transformer T, as indicated by the solid lines in Fig. 6.

Upon movement of the master controller MC to its second operative position b, a circuit is established from the contact segcontrol finger 49, conductor 50, train-line conductor 51, conductors 52 and 53 and the parallelonnected actuating coils of'the switches R1 and B2 to the negative conductor 36.

The resistors BB1 and BB2 are thus short-circuited'to effect a predetermined degree of acceleration of the motors, as indi cated by the dotted lines in Fig. 6.

The transition of the pairs of motors to the doubly-fed connection may then be effected automatically in the following manner: A circuit is established from conductor 52, interlock R1in and R2in, as soon as the corresponding switches have closed, conductors 54, interlock 5-out-, conductors 55 and 56, interlock C'O,-14-All'- in, auxiliary contact members 57 .of the limit switch L2, provided the motor current has decreased to a redetermined value to-allow the limit switc ii. to occupy its lower position, and conductor 58 to a junction-po' 9, w ence one circuit is completed through conductor 60, interlock 61 B1out, conductor 62, interlock (JO-10-All-in and the actuatin coil of the switch B1 to thenegative con uctor36, and completed from a h t rough d the actuating coil of the switch B2 to conductor 36. s soon as the switches B1 and B2 are closed, holding circuits therefor a second circuit is drops to its lower position. The main circuit connections at this time are illustrated in Fig. 7.

Upon closure of the switch 3, a circuit is established from conductor 54, through conductor 72, and 3'in to trainline conductor 74 wlnch is connected to cirf a multiple-unit the closure of are formed, comprising conductors 62, int e transition of the motors in the other veterlock 61B1in and conductors 66 and. hicles to the doubly-fed connection at subfor the switch' B and comprisin stantially the same time as the change is conductor 65, interlock 64-B21n, and coneffected in the system illustrated. It is beuctors 6 8 and 56 for the switch B2. lieved that this operation will be sufliciently As soon as the switches B1 and B2 have amiliar to those skilled in the art to obviclo a circuit is established from conducate the necessity of any further illustration tor 68' throug conductors 69 and 70, interor description. locks B1-in an B2in, conductor 71, in- It will be noted that the master controller Q2 are then 0 $1011 from the r control circuit of the interlock 3-out.

Attention is directed to the fact that the preponderating actuating coils of the limit hes L1 and L2 are respectively connected in circuit with the commutating field windings of the respective airs of motors, whereby the transition of t e motorsv to the doubly-fed connection, as just described, is eifected when the current in the commuwlindings reaches the value to permit of good commutation during the transition, which will ordinarily occur attained what may be heir synchronous speed. It should also be noted that, when the change-over switch CO occupies its All-in position, the auxiliary contact members of the limit are short-circuited by the inter- -in, whereb system during completed through proper complished automatically,

ect more stable motors to the doublye connection, whereby the transition is d automatically under the best commutating conditions, such automatic operation being preferable, as will be understood.

owever, if, f 0t erwise energize the train-line conductor e motors in other vehicles, such operation may be effected by actuating the controller M0 to its position 0, whereupon the contact segment 24 engages control finger 75, and circuit is conductor 76 to the trainine conductor 74. bus, in the preferred operation, the transition of motors on other vehicles to the-doubly-fed connection is acposition a of the master t e controller, at the time, occupies its preceding position I).

however, limit switch L2 does not fall he master controller is moved forward, hing occurs when contact ismade with position 0. he controller to the position so, intelloc 31n, conductor 81 an interlock 2-out and closes the switch 2, raising the motor voltageclosed position by a locking circuit from the conductor 69 through the interlock 2-in. The switch 1 thereupon opens by the exclusion from its operating circuit of the interlock 2out.

Movement of the controller to the position e closes a circuit 85, conductor 86, interlock 1-out, and the actuating coil 5 to the main 36, closing the I switch 54ml im osing maximum volta rep lsion by causing by causing the limit settlng switch 1 is opened by sion connection to. an

.if the master controller is moved too upon the motor w connection thereof;

In the circuit of the. aforementioned application, the movement of the master controller to the position 1, would energize the train-line conductor 89, and close the switch 4, thus passing from a' high-voltage repulintermediate middletap connection, with a resultant abrlipt change in speed and severe sparking. y the present system, this action is prevented the actuating coil of the switch 4 to be energized through an interlock 5-in located on the drawing in proximity to the limit switch'Ll and also through the contacts of the limit switch L2. By this means, rapidly from the posltion e to the posltion f, nothing happens until the speed has sufiiciently increased and the motor current sufliciently decreased to permit the limit switch L1 to fall. The first fall of said limit switch closes the switches B1 and. B2 and, immediately thereafter, scribed in the companion application, and thus establishes the low-voltage, mid-tap connection. The closure of the switch 3 opens the switches C1 and moves the repulsion connection shown -1I1 Fig. 8. The switch 4: is not closed at this time, not only because the interlock 3in is included in its circuit but also because it is interlocked at 61-in or 64 in. The next fall of the limit switch L1 energizes the actuating winding of the switch 4:, closing the same and raising the mid-tap voltwhereupon, movement of the master controller to the position 9 closes the switch 6 and permits full speed doubly-fed operation, as indicated in Fig. 9.

In the above-described semi-automatic acceleration, smoother operation is obtained for the differenswitches L1 and L2 to be lower in the upper speeds than in the lower speeds and, for this purpose, the auxiliary or subordinate coils 92 and 93 thereof are connected in shunt to the actuating coil of the switch 1, as shown. When, therefore, the the exclusion from the circuit thereof of the interlock 2out upon the movement of the master controller to the osition d, said subordinate or opposing lim- 1t switch 0 crating coils are deenergized,

roducing t e efiect of a reduction in t e limit setting.

It will be noted that by our system, with normal load, the change-over from repulsion to doubly-fed connection will occur at or about the third notch but, if the load is abnormally heavy, or if the master'controller is moved ahead too rapidly, the repulsion connection may be maintained until the sixth or seventh notch. When, however,

tial limit fi ile still maintaining t ethe switch 3, all as deand thus r e- A as, since 1,s11,aue

' the automatic change-over occurs, it takesplace to the initial mid-tap connection and.

thereafter there is automatic mid-tap a'cceleration until the master controller is caught up with.

Assuming that, because of an accident or for any other reason, it is desired to'cut the motors M1 and M2 out of operation, the change-over switch CO is moved to its second position marked M1 and M2-out whereby an interlock 11 the interlock 11 of the change-over switc while the interlocks CO-10 and CO+12 are'rendered inoperative by reason of the movement of the switch 'to its newposition. Consequently, the switch 7 and B1 cannot be closed, and only the motors ha g the armatures M4 are operative.

Moreover, in the second position of the change-over switch CO, an interlock 13* is.

switch L1 are no longer short-circuited by.

the interlock (JO- 14 there will be no fluttering action of the limit switches, inasmuc the circuit of the motors having the armatures M1 and M2 is dead, the switch L1 will remain in its lower position throughout the operation of the system.

If it is desired to exclude the other pair of motors from the circuit, the-change-over switch CO is operated to its third position marked M3 and Ma -out whereby interlocks 10 and 12 are substituted for in locks 10 and 12, while the interlocks 11 and 13* V are excluded from ,circuit. The switches A2,

operative, and only the circuitbf the motors having the armatures M1 and M2 may be employed. At the same time, an interlock (DO-15 bridges control fingers 96 and 97 of the change-over switch, whereby the interlock (JO-15 is lock B2-in to permit operation 0 switch 3, irrespective of the switch B2. 'Since the interlock (IO-44: is excluded from circuit and the limit switch L2 will remain down, the transsition of the motors having the armatures M1 and M2 to the doubly-fed connection will depend upon the position of the limit switch L1, which, in the other positions of the change-over switch, is inoperative.

While we have shown our simplest and preferred-form,-

substituted for the interf the it is not so 8 and B2 are thus rendered inof the inoperativeness invention in its limited but'is susceptible of various minor 5. The combin changes and modifications without departergyand an el ing from the spirit thereof, and we desire, producing two difl'er therefore, that only such limitations shall therebetween, placed thereupon-as are imposed by the control appara prior art or indicated in the appended be manually s claims. one type of 00 We claim as our invention: conditions h 1. The combination with a source of alstage, when ternating currents, of an alternating-curconnections rent motor of the compensated, commutator means 'whereby the initi f connections exceeds the last motor until the load current has fallen to ergy and an electric m a predetermined value, when transition to forming t i a doubly-fed connection is automatically efthere'betw the initial speed with doubly-fed operation ually started and at all times slightly exceeds the last speed of with repulsion operation.

2. The combination with a source of alwhen transition t ternating currents, of an alternatingnections is automa current motor of the compensated, comwhereby, mutator type, means for forming conlayed, the nections therebet'ween, said means embodyautomatically re mg a current-limit switch and attendant control apparatus whereby said motor may ergy and an be manually started and accelerated as a prod repulsion motor until the load current has spond' fallen to the setting of said limit switch, t1on when transition to doubly-fed operation is sition from th effected, and means whereby, if said transicertain stage ing step is reached.

tor connectlons, and means for automati- In test cally changmg the conditions of operation subscribe 16.

ave reached a p transition to the 0th is automatica transition is g of said limit ation with a ctric motor,

later stage. The combination ing certain accelerating connections for said nating current, of a motor, a relay responsive to predetermined motor of the commu motor-current conditions for automatically producing connectio e ecting a transition in said motor connecsponding to repulsio tions, and means for automatically changduction 0 ing the setting of said relay if said transiswitch for tion is not effected before a certain acceleratfrom the one to the 0th at a certain stag e combination with an alternatingsaid n alternat tator type, s therebetw n and transform and a cnrren normally e ting the tran er set of connections e motor accel g responsive t a source of enmotor, of means for fconnectlons fi'ected, and peed with the at all times speed with the first and means switch is source of enof means for etween corre- With a source of altering-current means for correer-consition eration, o relatively e have hereunto 9th day of F eb., 

